Research into Edge Drop of Cold Rolled Strip and Its Influencing Factors

Edge drop is a widespread problem in cold rolling, which affects directly the size of strip side scrapping and reduces strip yield. To reduce it, the mechanism of edge drop is elaborated detailedly, and the elastic-plastic FEM model to develop with the software MARC simulates the rolling process on 4-high cold mill. The fact that the calculated results of rolling force are basically close to the measured data proves the model´s accuracy and dependability. Using this model, the author systematically analyses the effects of edge drop´s influencing factors such as reduction rate, friction coefficient, entry thickness and entry width. The results show that edge drop increases with the increment of reduction rate, friction coefficient and entry thickness, in addition, edge drop firstly increases and then decreases with the increment of entry width.